EP0240620B1 - Ducted flow leak detection - Google Patents

Ducted flow leak detection Download PDF

Info

Publication number
EP0240620B1
EP0240620B1 EP86202373A EP86202373A EP0240620B1 EP 0240620 B1 EP0240620 B1 EP 0240620B1 EP 86202373 A EP86202373 A EP 86202373A EP 86202373 A EP86202373 A EP 86202373A EP 0240620 B1 EP0240620 B1 EP 0240620B1
Authority
EP
European Patent Office
Prior art keywords
leak
duct
fluid
directing
arrangement
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP86202373A
Other languages
German (de)
French (fr)
Other versions
EP0240620A1 (en
Inventor
David Henry British Aerospace Public Lancaster
William Roger British Aerospace Public Bostock
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BAE Systems PLC
Original Assignee
British Aerospace PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by British Aerospace PLC filed Critical British Aerospace PLC
Publication of EP0240620A1 publication Critical patent/EP0240620A1/en
Application granted granted Critical
Publication of EP0240620B1 publication Critical patent/EP0240620B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
    • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
    • F17D5/00—Protection or supervision of installations
    • F17D5/02—Preventing, monitoring, or locating loss
    • F17D5/04—Preventing, monitoring, or locating loss by means of a signalling fluid enclosed in a double wall

Definitions

  • This invention relates to ducted flow leak detection systems. More particularly it relates to an arrangement for detecting and isolating leaks in an aircraft air conditioning system.
  • the temperature of the air passing through the ducts may be of a high order.
  • the system may be drawing hot air as 'bleed' flow from the aircraft engines at a temperature in the region of 250°C.
  • the resulting loss of fluid may be detrimental. This may impair the effectiveness of the air conditioning system throughout the aircraft, or, perhaps more importantly, since duct systems in aircraft frequently lie closely adjacent to other systems or load carrying structures, these may be seriously affected by the impingement of hot air upon them or its mere circulation in close proximity.
  • One known means of leak detection is by the use of sensing wires able to detect an increase in localised temperature and, when a pre-determined temperature is exceeded, initiate a shut-off sequence, thus isolating the flow in that part of the system in which the leak occurs.
  • the wire which is available in a range of pre-set operating temperatures is located to run along the path of the ducts on adjacent structure but not too close such that its setting temperature is exceeded.
  • the selected setting temperature of these discrete sensing wires must he approximately mid-range between the inside temperature of the duct and the maximum ambient temperature of the duct surrounding.
  • the leak may occur in a position within the duct remote from the location of the sensing wire.
  • DE-A-1525646 discloses a leak detecting and containment arrangement for an oil carrying pipeline. Each pie section is surrounded by a jacket defining a space therebetween. Any leakage, either in a pipe section or at a junction between two sections, is contained within this space. In this arrangement, however, the leak sensors must be located within this space and thus close to the pipeline, but in a high temperature ducted flow system, as discussed above, this is an undesirable arrangement.
  • an arrangement for detecting and isolating leaks in a high temperature ducted fluid flow system said arrangement including:-
  • Figure 1 illustrates an air-conditioning duct mounted on the front spar of an aircraft wing.
  • Figure 2 is a pictorial arrangement of a duct joint assembly in accordance with the invention.
  • Figure 3 shows a front elevation on a typical duct joint assembly in accordance with the invention where indicated at 'Detail 3' in Figure 1.
  • Figure 4 is a vertical section through the typical joint assembly about a line 4-4 in Figure 3.
  • Figure 5 is a further vertical section through the same joint assembly about a line 5-5 in Figure 3.
  • Figure 6 is a transverse section through the same joint assembly about a line 6-6 in Figure 3.
  • Figure 1 illustrates an aircraft arrangement including a fuselage 2, the partial span of an aircraft wing 1 viewed on the front face of a wing front spar 3.
  • An air-conditioning duct assembly 4 extends inboard from the engine 'bleed' air inlet opening 5 and passes into the fuselage 2 at 6 where it communicates with the aircraft air-conditioning system (not shown).
  • the air-conditioning duct assembly 7 includes interconnected duct portions 7a, 7b, 7c, 7d respectively through which a supply of air is 'bled' or tapped from the aircraft engine supply source 8 at a temperature substantially 250°C.
  • each duct termination configured to include annular pipe coupling 11 shown in partial section here. It is common practice to contain each duct portion in concentric insulating lagging 12 of greater diameter than that of the duct to give an insulating air space 13 but terminating a short distance from each duct end to allow adequate clearance for coupling adjacent duct portions.
  • the duct lagging need only be of a suitable material having the required insulating properties
  • the material selected is one which will additionally have properties capable of withstanding pressure in the event of a duct fracture, for example a lagging material of glass-fibre wool 12a with an outer wrapper of stainless steel 12b, .006" or .008" thick. This ensures that the leaking high temperature air flow will be constrained within the lagging 12 and to flow in a controlled manner lengthwise towards one end.
  • the leak directing apparatus 16 includes a concentric metallic muff 17 preferably comprising a pair of flanged semi-circular muff portions 18 and 19 of a length exceeding the distance 20 between adjacent lagging portions and including annular sealing rings 22, sealingly engaging the lagging portions 12.
  • the semi-circular portion 19 of the muff 17 includes a welded attachment bracket 23 which provides a suitable bolted attachment 24 to the aircraft structure.
  • the semi-circular muff portion 18 includes a longitudinal fluid outlet slot 25.
  • the slot 25 as depicted in Figure 2 is illustrated in diagrammatic form it corresponds to that shown in the more formal representation of Figure 3 but particularly illustrates that the slot 25 is positioned such that it aligns with the sensing wire 26 which is located to the apparatus 16 by attachment P-clips 27.
  • the muff portion 18 does not attach to the muff portion 19 but to a longitudinal heat shield 28 located to the wing structure behind the duct. It is the lower flange of this heat shield together with that of the muff portion 18 spaced apart by means of spacing packings 29 which determine the slot 25.
  • the heat shield 28 comprises quite independent components and although they occur in structurally sensitive areas such as the wing front spar they are not an essential feature of the invention.
  • the sensing wire 26 although only depicted locally, runs along the path of the ducts on adjacent structure but not too close to the duct such that its setting temperature is exceeded.
  • the significance of the present invention is in the location of the sensing wire 26 relative to the slot 25 such that leak flow passing into direction apparatus l6 will impinge directly on the sensing wire when it subsequently passes through the slot 25.
  • the apparatus by encompassing a duct to duct joint may advantageously also detect any inadvertent leakage from the joint such as may be due to a faulty seal 10 in coupling 11.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Thermal Insulation (AREA)
  • Measuring Temperature Or Quantity Of Heat (AREA)

Description

  • This invention relates to ducted flow leak detection systems. More particularly it relates to an arrangement for detecting and isolating leaks in an aircraft air conditioning system.
  • It is known, in connection with ducted systems carrying high temperature air, for example, to provide means for detecting the presence of leakages within such systems which may be inadvertently caused by a number of factors. The temperature of the air passing through the ducts may be of a high order. For example, the system may be drawing hot air as 'bleed' flow from the aircraft engines at a temperature in the region of 250°C. In the event that a leak develops, for whatever reason, in a duct wall or in a mechanical joint between adjacent duct portions, the resulting loss of fluid may be detrimental. This may impair the effectiveness of the air conditioning system throughout the aircraft, or, perhaps more importantly, since duct systems in aircraft frequently lie closely adjacent to other systems or load carrying structures, these may be seriously affected by the impingement of hot air upon them or its mere circulation in close proximity.
  • One known means of leak detection is by the use of sensing wires able to detect an increase in localised temperature and, when a pre-determined temperature is exceeded, initiate a shut-off sequence, thus isolating the flow in that part of the system in which the leak occurs. The wire, which is available in a range of pre-set operating temperatures is located to run along the path of the ducts on adjacent structure but not too close such that its setting temperature is exceeded. The selected setting temperature of these discrete sensing wires must he approximately mid-range between the inside temperature of the duct and the maximum ambient temperature of the duct surrounding. However, as a result of these parameters it may be difficult to detect a leak if the differential temperature from inside to outside is very small; this situation occurs at the joints. Furthermore, the leak may occur in a position within the duct remote from the location of the sensing wire.
  • DE-A-1525646 discloses a leak detecting and containment arrangement for an oil carrying pipeline. Each pie section is surrounded by a jacket defining a space therebetween. Any leakage, either in a pipe section or at a junction between two sections, is contained within this space. In this arrangement, however, the leak sensors must be located within this space and thus close to the pipeline, but in a high temperature ducted flow system, as discussed above, this is an undesirable arrangement.
  • It is the object of the present invention to provide means in which the leakage flow issuing from a fractured or leaking duct is effected in such a manner that a high temperature differential is attained and directionally controlled such as to ensure impingement upon a heat sensitive sensing wire mounted externally although adjacent, to the leak directing means.
  • According to the present invention, there is provided an arrangement for detecting and isolating leaks in a high temperature ducted fluid flow system said arrangement including:-
    • duct means (7) through which fluid flow can take place, coupling means (10,11) interconnecting at least two duct means located substantially end to end, duct insulation means (12) extending over substantially the greater lengthwise portion of said duct means (7) and concentrically disposed about said duct means to define an insulating air space and leak containment means (13), blanking means (14) located at each termination of said duct insulation means to close-off said insulating air space (13), leak directing means (16) and leak sensing and isolating means (26) one of said blanking means (14a) including fluid venting means (15) in communication with said leak directing means (16), said leak directing means (16) being disposed concentrically about said coupling means (11) and extending longitudinally to sealingly overlap at least the termination of said duct insulation means (12) such that if a fluid leak occurs in said duct means (7) said leakage flow will be contained within said insulating air space and constrained to flow through said fluid venting means (15) into the space encompassed by said leak directing means (16) the arrangement characterised in that said leak directing means (16) includes fluid outlet means (25) and said leak sensing and system isolating means includes a heat sensitive sensing wire (26) lying external to but adjacent said leak directing means (16) and fixedly located in alignment with said fluid outlet means (25) whereby said leakage flow will be ejected through said fluid outlet means (25) and impinge directly upon said heat sensitive sensing wire (26).
  • One embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings in which, Figure 1, illustrates an air-conditioning duct mounted on the front spar of an aircraft wing.
    Figure 2, is a pictorial arrangement of a duct joint assembly in accordance with the invention.
    Figure 3, shows a front elevation on a typical duct joint assembly in accordance with the invention where indicated at 'Detail 3' in Figure 1.
    Figure 4, is a vertical section through the typical joint assembly about a line 4-4 in Figure 3.
    Figure 5, is a further vertical section through the same joint assembly about a line 5-5 in Figure 3.
    Figure 6, is a transverse section through the same joint assembly about a line 6-6 in Figure 3.
  • Referring to the drawings, Figure 1 illustrates an aircraft arrangement including a fuselage 2, the partial span of an aircraft wing 1 viewed on the front face of a wing front spar 3. An air-conditioning duct assembly 4 extends inboard from the engine 'bleed' air inlet opening 5 and passes into the fuselage 2 at 6 where it communicates with the aircraft air-conditioning system (not shown). The air-conditioning duct assembly 7 includes interconnected duct portions 7a, 7b, 7c, 7d respectively through which a supply of air is 'bled' or tapped from the aircraft engine supply source 8 at a temperature substantially 250°C.
  • Interconnection between adjoining duct portions, for example 7b and 7c is illustrated in Figure 6, each duct termination configured to include annular pipe coupling 11 shown in partial section here. It is common practice to contain each duct portion in concentric insulating lagging 12 of greater diameter than that of the duct to give an insulating air space 13 but terminating a short distance from each duct end to allow adequate clearance for coupling adjacent duct portions. Although for purposes of insulation the duct lagging need only be of a suitable material having the required insulating properties, in the present invention the material selected is one which will additionally have properties capable of withstanding pressure in the event of a duct fracture, for example a lagging material of glass-fibre wool 12a with an outer wrapper of stainless steel 12b, .006" or .008" thick. This ensures that the leaking high temperature air flow will be constrained within the lagging 12 and to flow in a controlled manner lengthwise towards one end. This is achieved as illustrated by particular reference to Figure 2 and Figure 6 which shows that the insulating air space 13 is blanked off by means of blanking pieces 14 at the termination of the lagging 12, the blanking piece 14a at one end incorporating a number of fluid venting holes 15 through which the air flow into leak directing apparatus 16. The leak directing apparatus 16 includes a concentric metallic muff 17 preferably comprising a pair of flanged semi-circular muff portions 18 and 19 of a length exceeding the distance 20 between adjacent lagging portions and including annular sealing rings 22, sealingly engaging the lagging portions 12. As illustrated in Figure 4, the semi-circular portion 19 of the muff 17 includes a welded attachment bracket 23 which provides a suitable bolted attachment 24 to the aircraft structure. The semi-circular muff portion 18 includes a longitudinal fluid outlet slot 25. Although the slot 25 as depicted in Figure 2 is illustrated in diagrammatic form it corresponds to that shown in the more formal representation of Figure 3 but particularly illustrates that the slot 25 is positioned such that it aligns with the sensing wire 26 which is located to the apparatus 16 by attachment P-clips 27. It should be mentioned that in the diagrammatic arrangement of Figure 2 the muff portion 18 does not attach to the muff portion 19 but to a longitudinal heat shield 28 located to the wing structure behind the duct. It is the lower flange of this heat shield together with that of the muff portion 18 spaced apart by means of spacing packings 29 which determine the slot 25. However, with reference to Figure 3 and Figure 5 in the preferred arrangement the heat shield 28 comprises quite independent components and although they occur in structurally sensitive areas such as the wing front spar they are not an essential feature of the invention.
  • The sensing wire 26, although only depicted locally, runs along the path of the ducts on adjacent structure but not too close to the duct such that its setting temperature is exceeded. The significance of the present invention is in the location of the sensing wire 26 relative to the slot 25 such that leak flow passing into direction apparatus l6 will impinge directly on the sensing wire when it subsequently passes through the slot 25.
  • In addition to sensing a leak resulting from an actual duct failure, the apparatus, by encompassing a duct to duct joint may advantageously also detect any inadvertent leakage from the joint such as may be due to a faulty seal 10 in coupling 11.
  • Finally, by virtue of its containment within the system, the flow issuing from the slot 25 will ensure the desired temperature differential for the discrete sensing wires and positively initiate isolation of the faulty system.

Claims (2)

  1. An arrangement for detecting and isolating leaks in a high temperature ducted fluid flow system said arrangement including:-
    duct means (7) through which fluid flow can take place, coupling means (10,11) interconnecting at least two duct means located substantially end to end, duct insulation means (12) extending over substantially the greater lengthwise portion of said duct means (7) and concentrically disposed about said duct means to define an insulating air space and leak containment means (13), blanking means (14) located at each termination of said duct insulation means to close-off said insulating air space (13), leak directing means (16) and leak sensing and isolating means (26) one of said blanking means (14a) including fluid venting means (15) in communication with said leak directing means (16) , said leak directing means (16) being disposed concentrically about said coupling means (11) and extending longitudinally to sealingly overlap at least the termination of said duct insulation means (l2) such that if a fluid leak occurs in said duct means (7) said leakage flow will be contained within said insulating air space and constrained to flow through said fluid venting means (15) into the space encompassed by said leak directing means (16) the arrangement characterised in that said leak directing means (16) includes fluid outlet means (25) and said leak sensing and system isolating means includes a heat sensitive sensing wire (26) lying external to but adjacent said leak directing means (16) and fixedly located in alignment with said fluid outlet means (25) whereby said leakage flow will be ejected through said fluid outlet means (25) and impinge directly upon said heat sensitive sensing wire (26).
  2. An arrangement according to Claim 1 in which said blanking means (14a) including fluid venting means (15) associated with respective interconnected ducts (7a, 7b, 7c) positions are in communication with common leak directing means (16).
EP86202373A 1985-12-23 1986-12-23 Ducted flow leak detection Expired - Lifetime EP0240620B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8531670 1985-12-23
GB858531670A GB8531670D0 (en) 1985-12-23 1985-12-23 Ducted flow leak detection

Publications (2)

Publication Number Publication Date
EP0240620A1 EP0240620A1 (en) 1987-10-14
EP0240620B1 true EP0240620B1 (en) 1991-02-27

Family

ID=10590212

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86202373A Expired - Lifetime EP0240620B1 (en) 1985-12-23 1986-12-23 Ducted flow leak detection

Country Status (7)

Country Link
US (1) US4750189A (en)
EP (1) EP0240620B1 (en)
BR (1) BR8606388A (en)
CA (1) CA1267330A (en)
DE (1) DE3677767D1 (en)
ES (1) ES2020660B3 (en)
GB (1) GB8531670D0 (en)

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8810877D0 (en) * 1988-05-07 1988-06-08 Score Uk Ltd Pipeline safety jacket systems
DE4109520A1 (en) * 1991-03-22 1992-09-24 Siemens Ag Device for sealing and monitoring space e.g. waste material dump - in which space is enclosed by two sealing layers between which are distance pieces and passages through which fluid medium is circulated
WO2003019069A1 (en) * 2001-08-30 2003-03-06 Flangeware Pty Ltd Pipe joint safety inspection device
US7413163B2 (en) 2004-04-30 2008-08-19 Senior Investments Ag Rack and pinion wheel drive for an industrial sliding blade damper
US7155961B2 (en) * 2004-06-04 2007-01-02 Senior Operations, Inc. Bleed leak detection system
RU2365889C1 (en) * 2007-12-29 2009-08-27 Шлюмберже Текнолоджи Б.В. Method for detection of gas leak point in underground pipeline (versions)
US8991437B2 (en) 2009-03-17 2015-03-31 Daher Aerospace Composite protective element for a thermally insulated pipe
FR2943397B1 (en) * 2009-03-17 2016-06-03 Daher Aerospace THERMAL INSULATION PROTECTION ELEMENT FOR PIPING
BRPI1016136A2 (en) * 2009-04-09 2019-09-24 Prad Research And Development Limited system for monitoring and detecting fluid invasion of an annular space of a pipe structure, and method for detecting fluid invasion of an annular space of a pipe structure.
US8967185B2 (en) 2010-07-21 2015-03-03 Senior Ip Gmbh Joint cover with manifold for duct leak detection system
FR2973341B1 (en) * 2011-04-04 2013-12-06 Airbus Operations Sas DEVICE FOR CONNECTING A SYSTEM FOR DETECTING AN AIR LEAK TO A SLEEVE ENVELOPING A AIR PRESSURE AIR PIPE OF AN AIRCRAFT
US8708554B2 (en) * 2011-05-12 2014-04-29 Arrowhead Products Corporation Leak detection apparatus for aircraft bleed air systems
US20130327127A1 (en) * 2012-06-08 2013-12-12 Airbus Operations Gmbh Leakage detection device and aircraft with a bleed air system and at least one leakage detection device
GB2553681B (en) 2015-01-07 2019-06-26 Homeserve Plc Flow detection device
GB201501935D0 (en) 2015-02-05 2015-03-25 Tooms Moore Consulting Ltd And Trow Consulting Ltd Water flow analysis
JP6501552B2 (en) * 2015-02-18 2019-04-17 三菱航空機株式会社 How to give robustness to piping structures, aircraft, and leak detection
JP6654350B2 (en) * 2015-02-18 2020-02-26 三菱航空機株式会社 Piping structure and aircraft
US10612404B2 (en) 2017-05-01 2020-04-07 Senior Ip Gmbh Joint cover with improved manifold block for duct leak detection system
JP7047478B2 (en) * 2018-03-09 2022-04-05 日本電気株式会社 Leakage detection system and leak detection method
US11112328B2 (en) * 2019-04-29 2021-09-07 Baker Hughes Oilfield Operations Llc Temperature based leak detection for blowout preventers

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR391175A (en) * 1908-06-13 1908-10-24 Alois Reimann Sleeve for heat insulated pipe flanges
GB1145295A (en) * 1966-05-20 1969-03-12 Ric Wil U K Ltd Pipe units for conduit systems
DE1525646A1 (en) * 1966-10-06 1969-07-17 Konrad Grebe Pipe string for pipelines
BE786714A (en) * 1971-08-02 1973-01-25 Gaz De France METHOD AND DEVICE FOR DETECTION AND LOCATION OF LEAKS OCCURRING IN LARGE CAPACITY INSULATED TANKS
JPS5522162A (en) * 1978-08-07 1980-02-16 Hitachi Ltd Sodium leak detecting method and device
JPS55163400A (en) * 1979-06-07 1980-12-19 Tokyo Sogo Keibi Hoshiyou Kk Liquid leak detection method in pipe line
DE3030296A1 (en) * 1980-08-09 1982-03-18 Reinhold Ing.(grad.) 6990 Bad Mergentheim Barlian DEVICE FOR DETECTING STEAM LEAKAGE
DE3110054A1 (en) * 1981-03-16 1982-10-14 G + H Montage Gmbh, 6700 Ludwigshafen PIPELINE SYSTEM, ESPECIALLY FROM HEAT-INSULATED REMOTE HEAT PIPES
DE3138355A1 (en) * 1981-09-26 1983-04-07 kabelmetal electro GmbH, 3000 Hannover Fitting for a conduit consisting of two metal tubes
DE3213821A1 (en) * 1982-04-15 1983-10-27 kabelmetal electro GmbH, 3000 Hannover Pipeline for transporting media harmful to the environment, and method of producing and laying the same
DE3246227A1 (en) * 1982-12-14 1984-06-14 Hochtemperatur-Reaktorbau GmbH, 5000 Köln Pipe-fracture detection system for pipelines with aggressive media under high pressure and high temperature

Also Published As

Publication number Publication date
GB8531670D0 (en) 1986-02-05
EP0240620A1 (en) 1987-10-14
US4750189A (en) 1988-06-07
ES2020660B3 (en) 1991-09-01
CA1267330A (en) 1990-04-03
BR8606388A (en) 1987-10-13
DE3677767D1 (en) 1991-04-04

Similar Documents

Publication Publication Date Title
EP0240620B1 (en) Ducted flow leak detection
US8328203B2 (en) Sealing system for exhaust-gas lines
US8708554B2 (en) Leak detection apparatus for aircraft bleed air systems
RU2561242C2 (en) Coupling jacket and manifold for pipes
EP0606696A1 (en) Fluid-carrying tube coupling with internal seal and leakage control
US4291905A (en) Duct seal
US20120073299A1 (en) High temperature manifolds for gas turbine engines
CN103597264A (en) Bulkhead fitting assembly
JPS6146654B2 (en)
JPS5831036Y2 (en) Internally insulated bellows structure
EP1867909B1 (en) Pipe penetration system
GB2107809A (en) Fuel pipe seal
US20130014840A1 (en) Pressurised hot air duct of an aircraft equipped with a device for detecting air leakage
EP3858736A1 (en) Aircraft pneumatic system
US5358284A (en) High temperature non-metallic expansion joint
JP2010230165A (en) Insulating protective element of piping
CN207554238U (en) Prevent the engine inlets structure of axial thermal expansion
US6070615A (en) Leakproof and fireproof tubing
WO1995001530A1 (en) Bellows expansion joint
US9228496B2 (en) Bleed air duct joint insulation means
EP2729726B1 (en) Encasement for heat transfer fluid conduits.
US4489960A (en) Flammable fluid leak deflector
JP7413382B2 (en) An improved fire protection device designed to be placed between one end of a mounting column for an aircraft turbomachine and the cowling of the turbomachine defining an interflow compartment.
CN110925524A (en) Displacement compensation device for heat insulation layer of high-pressure pipeline and installation method thereof
GB2226417A (en) Vent nozzle assembly for ducted flow leak detection system

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19861223

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT

17Q First examination report despatched

Effective date: 19880610

ITF It: translation for a ep patent filed

Owner name: BARZANO' E ZANARDO ROMA S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR GB IT

REF Corresponds to:

Ref document number: 3677767

Country of ref document: DE

Date of ref document: 19910404

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19931110

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19931116

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19931122

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 19931203

Year of fee payment: 8

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19941223

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF THE APPLICANT RENOUNCES

Effective date: 19941224

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19941223

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19950831

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19950901

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20010402

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20051223